In this paper, we report a fiber-optic pressure sensor fabricated by three-dimensional (3D) printing of glass using direct laser melting method. An all-glass fiber-housing structure is 3D printed on top of a fused silica substrate, which also serves as the pressure sensing diaphragm. The usage of fiber‐optic sensors has flourished in many fields over the past 30 years due to the fiber‐optic's inherent advantages: cost‐effectiveness, miniaturized size, light weight, and immunity to electromagnetic interference. The aim of the SPIE Field Guides is to distill this information, providing readers with a handy desk or briefcase reference that provides basic, essential information about optical princi-ples, techniques, or phenomena, including definitions and descriptions, key. The functionality of an optical fiber depends on its two main components: the core and the cladding. The core is the innermost, light-carrying section, typically made from ultra-pure silica glass that is doped to achieve a specific refractive index. Initially conceived as a medium to carry light and images for medical endoscopic applications, optical fibers were later proposed in the mid 1960's as an adequate information-carrying medium for. The core of most FOS technologies, whether they use FBGs or not, is interferometry. Simply put, interferometry is a family of techniques in which waves are superimposed to extract information about the waves. In FBG-based systems, light reflected back to the interrogator (light source) gets. The invention discloses an apparatus (100) to fabricate U-bent fiber optic sensors, transducers and waveguides, using laser assisted technologies as heat source. The apparatus includes a heating source (110) and a robotic articulate arm (130) that may modify the geometry of an optical fiber (150).